#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	float b = 0;
	int t = 0;
	float  sum;
	scanf("%f %d", &b, &t);
	float n;
	switch (t)
	{
	case 1:
		n = 0.00315;
		break;
	case 2:
		n = 0.0033;
		break;
	case 3:
		n = 0.00345;
		break;
	case 4:
	case 5:
		n = 0.00375;
		break;
	case 6:
	case 7:
	case 8:
		n = 0.0042;
		break;
	}
	sum = b + b * n * t * 12;
	printf("%.2f", sum);
	
	return 0;

}

